High-frequency low-dielectric hydrophobic polyimide composite film as well as preparation method and application thereof

The invention discloses a high-frequency low-dielectric hydrophobic polyimide composite membrane as well as a preparation method and application thereof. Hollow silicon dioxide microspheres with uniform particle size are prepared, and the surfaces of the hollow silicon dioxide microspheres are organically modified by adopting a silane coupling agent grafted with hydrophobic groups; the hollow silicon dioxide microspheres with hydrophobic effect and good compatibility with a polyimide matrix are obtained. And then dispersing the hydrophobic modified hollow silicon dioxide microspheres in a polyamide acid solution by a physical doping method, and carrying out imidization to obtain the polyimide composite membrane. The film has the excellent characteristics of low dielectric constant, low thermal expansion coefficient, high hydrophobicity and the like, and can be widely used in the fields of high-frequency and high-speed base materials and the like. 本发明公开了一种高频低介电疏水聚酰亚胺复合膜及其制备方法和应用，通过制备粒径均匀的空心二氧化硅微球，采用接枝疏水基团的硅烷偶联